Sinker cover mechanism for circular knitting machines



Nov. 28, 1967 V.'SANTON| 3,354,673

SINKER COVER MECHANISM FOR CIRCULAR KNITTING MACHINES Filed Aug. 11,1965 H e. i

10 am I \V/ V I l y I ATTORNEY United States Patent 3,354,673SINKER-COVER MECHANISM FOR CIRCULAR KNITTING MACHINES Vinicio Santoni,Via Amba DOro 9, Brescia, Italy Filed Aug. 11, 1965, Ser. No. 478,921Claims priority, application Italy, Aug. 14, 1964, 50,295, Patent721,769 5 Claims. (Cl. 66-107) ABSTRACT OF THE DISCLOSURE A circularstocking machine is described including a needle cylinder, a sinkercrown secured thereto and formed with a peripheral rib, aradially-extending flange secured to the sinker crown and defining withthe peripheral rib a circumferential groove around the sinker crown, asinker cover overlying the sinker crown and radially spaced from itsperipheral rib, and a plurality of rolling bearing members disposed inthe groove and in contact with the sinker cover. The flange serves as ananti-friction bearing resisting the relatively small axial stresses,while the rolling bearing members resist the high radial stresses.

The present invention relates to circular stocking machines, an objectof the invention being to provide an improved guide for the sinkercover.

It is well known that the radial guide of the sinker cover in circularstocking machines occurs by sliding said cover over the outersinker-crown, as if the cover were a bushing and the outer sinker crownwere the pin rotating in said bushing.

This guide system, besides producing a rapid wear of surfaces cominginto contact with each other, has the disadvantage that it is necessaryto increase the mounting plays to the detriment of precision andaccuracy of the entire assembly. This is particularly true in the latestmulti-feed machines where, because of more sliding of the sinkers on theouter crown, at each revolution of the machine a considerableoverheating of the crown occurs with consequent expansion.

A known system devised to minimize sliding friction consists in guidingthe cover with three rollers arranged at 120 on the outer crown circularwall. The axes of the rollers are integral with the cover itself, andthe outer crown circular wall is of larger diameter than the cover. Onaccount of the fastening system of the cover, which is held firm at onepoint, and of the thrust given by the resistance to sliding of thesinkers, it usually happens that the whole load is concentrated on twoof the three rollers. The support points, which are in fact two lines nomore than 67 mm. long, are of too reduced dimensions to ensure that nocrushing or deformation occurs on the portion of the outer crown onwhich the rollers rest.

The aforementioned disadvantages are largely avoided by the machineaccording to the present invention, comprising in a well known manner asinker cover sliding over an outer sinker crown, and substantiallycharacterized in that the sinker crown is formed with a circumferentialgroove and receives rolling members interposed between the sinker crownand the sinker cover in the zone of radial contact therebetween.

3,354,673 Patented Nov. 28, 1967 According to a further feature, thesinker crown includes at least two parts rigidly connected to each otherto form the groove for the rolling members, said members projecting fromthe groove into contact with the sinker cover.

The present invention will be better described by reference to theaccompanying drawings in which FIG. 1 illustrates an axial view, withparts in section, of a preferred embodiment, and FIG. 2 is an enlargedfragmentary view of a variation.

As shown in the drawings, the needle cylinder 1 is associated with theouter sinker crown 2 via locking plates 3 tightened by means of screws4. The sinker crown 2 houses the sinkers and has secured thereto aradiallyextending flange 5, for example, by means of screws 6. Flange 5defines, with a peripheral rib 11 on sinker crown 2, a circumferentialgroove for receiving rolling bearing members in the form of rollers 7.Rollers 7 are rotatable on axes parallel to the axis of rotation of thesinker crown, the roller axes being freely movable along the groovecontaining the rollers, as in roller bearings of known types.

On the crown 2 and the flange 5 is supported the sinker cover 8, whichis held in position overlying the crown via the clamps 9 locked on thecover 8 by means of screws 10. The clamps 9 are fixed to underlie theflange 5, so as to avoid any relative axial displacement between cover 8and crown 2, while still permitting the latter to freely rotate togetherwith its flange 5. In this manner, during rotation of the cylinder 1with crown 2 and flange 5, the main stress of friction against the cover8 essentially occurs through the rollers 7 which provide support inradial direction. For this purpose, the surface of rib 11 of the crown 2is not in contact with the cover 8, but is of slightly smaller diameterthan the inside diameter of said cover 8 so that the cover is radiallyspaced from the crown but is in contact with the flange 5. The flangeserves not only as a part of the means for housing the rolling bearingmembers, but also as an anti-friction bearing resisting the axialstresses, the latter being relatively small compared to the high radialstresses resisted by the rolling bearing members.

The crown 2 may be made of metal, such as steel, or of any othersuitable material. The flange 5 may also be of metal, but is preferablyof plastic material, for example 11 lon.

In the variation of FIG. 2, the rolling members are in the form of balls7 and may be spaced from each other by a containment guiding cage 12having a separator 13. Conventional ball bearings could also be used inwhich the balls 7' are mounted in cages of known type.

It is to be understood that the present invention is not restricted tothe particular embodiment described in the foregoing description, but issubject to many changes and modifications, depending upon individualdesign, without however departing from the spirit and scope of theinvention as defined in the following claims.

I claim:

1. In a circular stocking machine, a needle cylinder, a sinker crownsecured thereto to rotate therewith, said sinker crown including aperipheral rib, a radially extending flange secured to said sinker crownand defining with said peripheral rib a circumferential groove aroundsaid sinker crown, a sinker cover overlying said sinker crown bearingmembers disposed in said groove 'in' contact with said sinker cover,whereby said flange serves with said peripheral rib for housing therolling bearing members and also for resisting the axial stresses, whilesaid rolling bearing members resist the high radial stresses.

2. A circular stocking machine according to claim 1, wherein said sinkercrown is made of steel and said flange is made of plastic.

3. A circular stocking machine according to claim 1, wherein saidrolling bearing members consist of rollers having axes parallel to thesinker crown rotating axis.

4. In a circular stocking machine according to claim 1, wherein saidrolling vbearing members consist of balls.

5. In a circular stocking machine according to claim 1, wherein saidrolling bearing members are spaced from each other by a containmentguiding cage.

References Cited UNITED STATES PATENTS 1,643,156 9/1927 Farmer 3081892,879,083 3/1959 COrSette 30835 X 3,192,741 7/1965 Hanel 66108 X3,271,835 9/1966 Hadley 2615 3,273,359 9/1966 Fregeolle 66108 X ROBERTR. MACKEY, Primary Examiner.

1. IN A CIRCULAR STOCKING MACHINE, A NEEDLE CYLINDER, A SINKER CROWNSECURED THERETO TO ROTATE THEREWITH, SAID SINKER CROWN INCLUDING APERIPHERAL RIB, A RADIALLY EXTENDING FLANGE SECURED TO SAID SINKER CROWNAND DEFINING WITH SAID PERIPHERAL RIB A CIRCUMFERENTIAL GROOVE AROUNDSAID SINKER CROWN, A SINKER COVER OVERLYING SAID SINKER CROWN ANDRADIALLY SPACED THEREFROM, AND A PLURALITY OF ROLLING BEARING MEMBERDISPOSED IN SAID GROOVE IN CONTACT WITH SAID SINKER COVER, WHEREBY SAIDFLANGE SERVES WITH SAID PERIPHERAL RIB FOR HOUSING THE ROLLING BEARINGMEMBERS AND ALSO FOR RESISTING THE AXIAL STRESSES, WHILE SAID ROLLINGBEARING MEMBERS RESIST THE HIGH RADIAL STRESSES.